Metaprogramming and instance variables

Hello,

I'm reading whys poignant guide to ruby at the momemt and am in the
chapter of metaprogramming. There is one thing in the Creature-Example
I don't understand.

A short example to exemplify
--- snip ---
class Foo
def self.method(val)
@var = val
p instance_variables
end
end

class Bar < Foo
method true
end
--- snap ---

Execution returns "[@var]". But since @var is an instance-variable,
where is is stored. Shouldn't it be set first when an instance is
allocated?

Thanks for help,
Michael

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